MUSCLE PHYSIOLOGY

Detailed explanation-1: -These contractions extend from the muscle fiber through connective tissue to pull on bones, causing skeletal movement. The pull exerted by a muscle is called tension, and the amount of force created by this tension can vary. This enables the same muscles to move very light objects and very heavy objects.

Detailed explanation-2: -Concentric contractions occur when the muscles shorten while generating force. An example of concentric contraction would be the upward pull during a pull up. Eccentric contractions occur when the muscles lengthen while generating force.

Detailed explanation-3: -Each skeletal muscle fiber contains filaments of actin and myosin that shorten the muscle and pull on tendons, which in turn pull on bones and move the body. These movements are described as pushes when the muscle moves away from the body or pulls when the muscle moves toward the body.

Detailed explanation-4: -Summary. According to the sliding filament theory, a muscle fiber contracts when myosin filaments pull actin filaments closer together and thus shorten sarcomeres within a fiber. When all the sarcomeres in a muscle fiber shorten, the fiber contracts.

Detailed explanation-5: -The term contraction is used generally to describe muscle force generation, and it highlights the fact that muscles are only capable of producing tensile force (or contractile force). If a single action potential is delivered to a muscle, then a brief burst of force is observed, termed the isometric twitch.